Compressor



A. GREENWALD OMPRES 5 OR Filed June 13, 1927 Patented Noe. 15,1927.

UNITED STATES PATENT-.QFFICE.

- W'HITEHEAD,

OIiD A. GBEENWALD, OF DETROIT, KIQHIGKN, ASSIGNOB OF DETROIT} MICHIGAN.

To rnomtas EDMPRESSOB.

Application filed June is, 1927. Serial 1a.

The invention relates generally to compressors for refrigerating apparatus an finds particular utility in a means for me renting dilution of oil in the crank case in the operation of compressors 3881101151 disadvantage has been commonly experienced by the leakage of gas past the piston into the crank case, thus building up pressure in the latter and diluting the oil contained therein and proving detrimental to the working parts of the apparatus. his objectionable feature is more than compensated iorin the present invention by the novel construction oi the compressor in which means is provided for permitting escape otthe gas leaking past the piston prior to its entrance in the crank case.

The inventionhas also among its objects to simplify, render more eficient and unprove generally devices of thischaracter and these as well as other objects, advantages and novel details of construction will be made more ap arent as this description proceeds, especial y when considered in connection with the accompanying drawings sponding parts,

, ed by means of a wrist pin 15 necting rod 16 to wherein,

Figure 1 pressor embodying my Figure 2-2 of Figure 1. I

tReferring nowto the drawings in which like reference numerals designate correthe reference character designates a compressor having. a crank case 11 containing 21 suppl of lubricant, and 12 y a. crank shaft journalled in suitable bearings is a sectional elevation of a com mvention, and

13. Formed, preferably although not nec-' essarily, integral withthe casing 10 is a cylinder 14 within which a piston 15 is reciprocably mounted. The piston is conncct and a conthe crank shaft 12. The

cylinder 14 is provided with a port 18 which communicates with a suitable. conduit (not shown) by means of which the refrigerant or the gas compressed in the chamber is conducted away. In the present instance the port 18 is connected to a condenser.

' As shown the cylinder 14 has a chamber 21 formed at one side thereof and provided 'with an intake opening cateswith the expansion vention is used as a p rt apparatus.

coils when the 'inoi a refrigerating 2 is a sectionalview taken on line.

' stantially its uppermost 22, which communi- Communication between the chamber 21 r downward or suction upon a compression stroke will be compressed therein and forced out through the port 18. @bviously upon the downward or suction stroke of the piston 15, a lower pressure is created in the cylinder 1t causing a: corresponding lower pressure to obtain in chamber 21 thus drawing the refrigerant in through the opening 22.

in practice, a certain percentage of gas contained in the cylinder 1% leaks past the p ston and into the crank case diluting the Oll contained therein, proving detrimental to the working parts of the apparatus as,

for example, the seal.

. In the present invention this objectionable feature is eliminated by the novel construction of the piston and wrist pin. As shown,

the wrist pin 15' is of hollow construction open at both ends, and the piston 15 is formed with aligned circumferential grooves 24 and 25 communicating with the wrist pin. Thus any gas that-leaks past the usual piston ring will be collected by the grooves 24 and 25 and will flow into the wrist pin, due to the fact that the depth of the grooves is substantially greater than the distance betwexzn the cylinder wall and the wrist pin seryes as a surge chamber or reservoir for the"gas which, upon entering the wrist pin, pressure therein until' the piston is in subposition, whereupon the gas will be discharged through the open ing' 23 and into the arresting chamber 21. w it will be readily ap:

parent that the gas leaking piston. In practice,

builds up a rclatiyely high "described and that such changes may he-resorted to when desired as fall within the scope of the claims.

What I claim as my invention is:

- 1. A compressor assembly including a cyl-e inder, a piston reciprocable in said cylinder having a passage for receiving the gas leaking past the piston, and a wrist pin having a recess therein communicating with the passage. I

2. A compressor assembly including a cyi inder, a piston reciprocable in said cylinder formed with a circumfe'rentially extending groove for receiving the gas leaking past the piston, and a hollow wrist pin communicating with the groove.

.3; compressor assembly including a cyl inder, an arresting chambereadjacent thereto and having a passage communicating there with, a piston reciprocablein said cylinder having a circumferentially extending groove for receiving the gas leaking past said piston, and means associated with said piston for conducting the escaped gas through said passage into the arresting chamber.

- In testimony inder, a piston reciprocable in said cylinder having a .circu nferentially extending groove for receiving the gas leaking past said piston, a hollow wrist pm communicating with said groove for collecting the escaped gas, and

an arresting chamber adjacent to said cylinder having a passage communicating there with operable. to conduct gas from said chamber into said cylinder in one position of the piston and to permit a discharge of the escaped gas entrapped in the wrist pin into'the arresting chamber in another position of the piston.

whereof I aiiix my signature. HAROLD A. GREEN WALD. 

